#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
#include<stdlib.h>
#include<stdio.h>
#include<stdlib.h>
int cmp(const void* e1, const void* e2)
{
    return *(int*)e1 - *(int*)e2;
}
int main()
{
    int a = 0;
    int b = 0;
    int c = 0;
    int arr[3] = { 0 };
    while (~scanf("%d %d %d", &a, &b, &c))
    {
        arr[0] = a; arr[1] = b; arr[2] = c;
        qsort(arr, 3, 4, cmp);
        if (arr[0] + arr[1] > arr[2] && arr[2] - arr[1] < arr[0])
        {
            if (arr[0] == arr[1] && arr[1] == arr[2])
            {
                printf("Equilateral triangle!\n");
            }
            else if (arr[0] != arr[1] && arr[1] != arr[2] && arr[0] != arr[2])
            {
                printf("Ordinary triangle!\n");
            }
            else
            {
                printf("Isosceles triangle!\n");
            }
        }
        else
        {
            printf("Not a triangle!\n");
        }
    }
    return 0;
}
